package com.z1.core.web.util;

import javax.servlet.http.HttpServletRequest;

public final class IpUtil {

	/**
	 * 获取客户端IP地址，针对Nginx等反代作处理
	 * @param request
	 * @return
	 */
	public static final String getIp(HttpServletRequest request) {
		String ip = null;
		
		//X-Forwarded-For：Squid 服务代理
		String ipAddresses = request.getHeader("X-Forwarded-For");
		if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
			//Proxy-Client-IP：apache 服务代理
			ipAddresses = request.getHeader("Proxy-Client-IP");
		}
		if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
			//WL-Proxy-Client-IP：weblogic 服务代理
			ipAddresses = request.getHeader("WL-Proxy-Client-IP");
		}
		if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
			//HTTP_CLIENT_IP：有些代理服务器
			ipAddresses = request.getHeader("HTTP_CLIENT_IP");
		}
		if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
			//X-Real-IP：nginx服务代理
			ipAddresses = request.getHeader("X-Real-IP");
		}
		
		//有些网络通过多层代理，那么获取到的ip就会有多个，一般都是通过逗号（,）分割开来，并且第一个ip为客户端的真实IP
		if (ipAddresses != null && ipAddresses.length() != 0) {
			ip = ipAddresses.split(",")[0];
		}
		
		//还是不能获取到，最后再通过request.getRemoteAddr();获取
		if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
			ip = request.getRemoteAddr();
		}
	    
	    return ip.equals("0:0:0:0:0:0:0:1")?"127.0.0.1":ip;
	}
	
}
